[template] Define the TemplateNumber constructor out of line

esphome/components/template/number/template_number.cpp

@@ -3,6 +3,8 @@
 
 namespace esphome::template_ {
 
+TemplateNumber::TemplateNumber() {}
+
 static const char *const TAG = "template.number";
 
 void TemplateNumber::setup() {

esphome/components/template/number/template_number.h

@@ -11,7 +11,8 @@ namespace esphome::template_ {
 class TemplateNumber final : public number::Number, public PollingComponent {
  public:
   // User provided, not "= default": `new(p) TemplateNumber()` would zero-fill .bss that is already zero.
-  TemplateNumber() {}
+  // Defined out of line so the member constructors are not inlined into every construction site.
+  TemplateNumber();
   template<typename F> void set_template(F &&f) { this->f_.set(std::forward<F>(f)); }
 
   void setup() override;